Traveling-grate furnace



(No Model.) i 2 Sheets-Sheet 1. H. RICHARDS.

TRAVELING GRATB FURNAGE.

Patented Oct. 16, 1894.

D ign fu: Nmrps wetens co, PHOTO-Unno.. wAsHNLToN, D. c4

WjzneSSES/ j a @imag PATENTy trice.,N

FRANCIS H. RICHARDS, CF HARTFORD,

CONNECTICUT, ASSIGNOR TO ECKLEY B. COXE, OFDRIFTON, PENNSYLVANIA.

TRAVELING-G RATE FU RNACE.

SPECIFICATIONiforming part of Letters `Patent No. 527,450I dated October 16, 1 894.

Application led June 1894.

`1o class employing a traveling grate or furnace floor, and in which. the fuel, ignited while spread in a layer upon the grate, `is subjected to successive air-blasts of successively varying pressures during the successive stages of I5 the combustion period, as described, for instance, in United States Letters Patent No.

499,716, granted toEckley B. CoXe, June 20, 1893.

In traveling-grate or traveling-floor furzo naces of this class as heretofore constructed,

it has been customary to supply air to the upper or fuel-carrying run of the traveling oor from fixed air-chambers located between the upper and lower runs of saidgrate, said z5 chambers being open at the ends thereof adjacent to the upper run of said grate; and, owing to the location of said chambers, more or less coal-dust or small fragments of 'coal would, during the traveling movement of the 3o grate, fall into said chambers through the upper run of said grate, thus necessitating a cleaning-out of the chambers from time to time.

The obj ect of my present invention is to provide inconnection with a furnace a traveling furnace-Hoor comprisingaseries of successive and independent hoor-beam air-boxes each having an inlet opening at one end thereof, means for imparting a traveling movement to 4o said furnace-floor, and means in position and adapted for supplying air tothe series of floorbeam air-boxes through the inlet openings at the ends thereof; also to so construct and organize said furnace-door that the floor-beam air-boxes thereof will be protected, ina great measure, from the warping influences of the heat and will also, in a practical degree, be self-cleaning, or, in other words, will,during the traveling movement thereof, discharge 5o any fragments of coal or analogous 4material which may have fallen into them.` l 4 lcross-section of the same, taken in line b--b,

` chambers and grate-bars or floor-plates.

sena No. 515,600. (No man In the drawings accompanying and forming apart of this specification, Figure l isasectional plan view of a traveling-grate furnace embodying my invention, portions thereof being broken away t0 more clearly show the construction of 'certain details thereof. Fig. Zisavertieal longitudinal section of the same, taken in line a-ct, Fig. l. Fig. 3 isa vertical 6o looking toward the right-hand in said figure. Fig. 4: is `an enlarged longitudinal section of a portion of the traveling grate, showing the construction and arrangement of the air- Fig. is a plan View, on an enlarged scale, of a portion of a grate of modified construction. Fig. 6 is a vertical longitudinal section of the same. Figs. 7, 8 and 9 are plan, side, and end` views, respectively, of one of the gratebars shown in Figs. l, 2, 3 and 4.

Similar characters designate like parts in all the figures.

In the preferred form thereof herein shown and described, my invention resides in the 75 combination, in a furnace, of a traveling furnace-floor comprising a series of success- -ive and independent `Hoor-beams each embodyingan inclosed air-chamber (which airchamber and floor-beam together will be hereinafter termed `the floor-beam air-box each air-'chamber having an inlet opening at one end thereof, means for imparting a traveling movement to the furnace-Hoor, and an air-supply apparatus in position and adapted for supplying air to the air-chambers through the inlet openingswthereof, al1 of which will be hereinafter more fully described. For illustrating the application and utility of my present improvement,l have shown the same applied to a furnace whose general construction is similar to that of the furnace shown and described inthe aforesaid Letters Patent No. 499,716. In the present instance, however, the furnace-chamber C is shown covered for a considerable portion of its length by a reverberatory roof, A. `Thefurnace-chamber C is inclosed at the sides and ends thereof by the usualside-walls, 2 ande", front end-wall, 3, and the rear wall or bridgewall, 7. A space is shown at the rear end of the roofA for the reception of a boiler or IOO other thing to be heated. In the front endwall 3 is a passageway, 5 throughwhich' the fuelis supplied to thegrate.

The ioor of the furnace consists of the upper run, l0, of an endless traveling grate, designated in a general way by G, and which is carried upon suitable grate-carrying wheelsy or chain-Wheels, 12 andA 14, that are supported upon shafts, 13 and 15, journaled in suitable bearings in the side-walls 2 and 4 of the furnace. As a means for actuating said shafts for imparting the required traveling movement to the furnace-floor, the shaft 13 is shown furnished with a worm-wheel, 4

that meshes with a worm, 4,1, on a drivingshaft, 42, journaled in bearings, 43 and 4:3 (shown infull lines in Fig. 1, and in dotted any'7 'suitablefsource o'fpewer".l 'f

Fory supplying fuelto the endless? gra'teG,

a hOpperfI-I, is' shownplaced' at the forward-5' endbfl lcheffurii'a'c'e"with' itsN delivering-en'df contiguou'stothepassagewvay5in the'front endLWall- 3.

Thenpperfandfiower rgnslio analyte-2 specti'velyg'of the traveling grate will prefr erably be supported" by rollers, 51 andil;

rev'olnbly supported "by rolleribeams52 i tand? 52'; secured 'tothe side#walls2l and@ of 'thej furnace. -Forjthepurpes'e bf protecting the sideledges of the furnace-nodi, and also for" preventingfine fuel passing l"over ythe *sideff edgesthereofythe sidevvalls of -theffurna'ceare" extended inward: verf'the i side-edgsffof Fig.` 3 yof 'the drawings."`

The traveling grate or furnace'iiooigin theA forni 'thereof herein' "shown, consists of la- Ase-fries of transverse chambeed orboxlik'e gratebar-supporting beams br door-beam air boxes," N, carrying theoor-plates M,*or` grate-bars i fpropfer of the furnacefoor, which'beams are preferablycarried'by a pair of 'endless chains, 50 -and@ 50,consisting,-f in the form thereof hereinshwn,Y of :a series 'of -link's,*63, l(see Figs; 1,2, 3,- 4 and 6,) `connec-ted""together byy pivot-pins or rivets; 63', preferably las'shown" in Fig.`4. In thisl preferred formftheiloorbearnair'boxes N have depending lugsa'trp'- posite ends at their under side, asfsho'wn ati 66,"whichif1ugs` are 1rivetedto the'side-"faces of oppositelinks of lthe two"chai`ns,*as most clearly shown in o In 'theforin 'thereof Ashown in Figs'.- v1, 2, 3

and4 of the drawingsgeac'h floor-beain`airv` box is open'at o'ne 'end and oneside thereof,"

as shown at: I20 yand-y` 21, respectively, andf is adapted` for relnbvably carrying a series yof grate-ibarsjlvf.' Thefopen side'of saidfloor' bea-nn air bex is shown having oppositeiyf-dis;

posed nwardly-projecting ""grate-bar-enga'g- `ing anges, 22 and23, and' the grate-bars M are shown'having central depending'anges, 24, 'which lare preferably'doveta'iled," as most clearly'sh'own in Figyli, andextend between and are engaged by the flanges 22 and 23 of `the floor-beamair box N.-

vof greater* or less area as required. t -In some cases, instead of providing the floor-beam air boxes N with removable gratebars M as shown in Fig.` 4, it may be desirable to employ aigrateibeamhaving four side` walls-,Fas shown zin Figs'. 5 and 6, and to per-f -forate the *outer-wall to form air# spaces; therefore it isA not desired tolimitthis tinvenbeam ain-box Ishown in Fig. 4 of the draw-A -ings, although the construction therein shown l'is preferable, as it permits the grate-barsu to be'readily removed and replaced,` in case*'of jacciden't'thereto, without the necessity of 'replacing an'f'entireflodr-beam airbox; it being tifon to the particulai` construction ofr'floorsiniply'necessary, when it is desired to vre- 1 -move"and replace-the grate-bars,1in the 'or' ganiza'tion shown in Fig. 4,. to slipsaid lbarsMAY off the grat'e-bez'tm' at theiopengendoffsaid bearnland replace themA in av likeI mannenas Twill "be `readily understood by referenceto Figs. 3 and 4 of the drawings.

f .o Byftheconstructiontand organization 'here-1 vin shownand'described it will be seen" that,

owing to the chambered construction of the IOO `grateLbealntis, the floor-is made up of a seriesof travelingfairfchambers" having 'open'ends `in close 'proximity to the inner face of one of'the-side'-walls o'f the furnaces As 'af'n'leansfor'supplying air to thetrav- "I'IO "elingfair-cha'mbers or to the interiorl` of the vcha'Ju-bered beams N at successive pointsin, and during the traveling movement thereof,

and;V to regulate'the'pressure'of the airblast suppliedr thereto 'at therequired points' in the fuel carried by the traveling furnace-Hoor or which,'in the formthereof herein shown, coni vv`sists of a series of fixed separated'compa'rt'- `length of thefurnace-chamber to secure the f best practical results in the combustion of the I grate,I have provided an air-sup'plyapparatus" ments; a, a', a2, a3, preferably of different areas,` locatedPat one'side ofthe upper run, 10, of the` traveling grate'c'ontiguous to the open ends of thefloo'r-beam air boxes and communicating Iwiththe' interior of saidtloor-beam airboxes'4 through'inlet openings,.b, b', b2, and b3, which register with the open ends of saidciioor-I Vbeam'ainboXes,as clearly shown' in Fi'gsl,

2 and'3 of the drawings.k Said'xed air-sup- 1130 ply compartments may be two'or more yin number," four of thembeing' shown in the presen't'ins'tance. notless than three'such. chambers. For supi In general I preferito usen.

y pipe, c, c', c2 and c3,^which communicateswith and terminates in a large supply-pipe, P, which will be connected with any suitable air-supply, as, for instance, an air-pump or blower.` (Not shown.) In some cases, it is preferable to connect said air-supply pipe P with the second fixed compartment a of the series so that the high pressure of the airblast will be supplied to the air-chambers ofthe hollow beams N at a `point approximately midway of the length of the furnacechamber, which point corresponds to the middie of the combustion-period of the fuel. Therefore said compartment a and the pipe c communicating there with will preferably be of greater area than the compartments a, a2 and a3 and their communicating pipes.

In practice, the best possible results in the combustion of the fuel are obtained by regulating the air-supply to the fuel so that at the ignition-period, or when the fuel is at that point adjacent to the receiving-end of the traveling grate, a low-pressure airblast of only suflicient pressure to gently blow the ignited fuel is supplied thereto at this point; andafter the fuel has passed the ignition-point, an air-blast of high-pressure is supplied thereto, which pressure is gradually reduced thereafter at successive points in the length of the furnacechamber, as fully described in connection with other means in the patent aforesaid; and to accomplish this result I have provided each supply-pipe c, c', c2 and c3, with regulating-valves, d, d', d2 and d3, respectively, by means of which the influx of air atsuccessive points in thelength of the furnace-chamber may be properly regulated to secure the requisite results at these points.

To prevent leakage of air at points between t the chambered beams N, each beam is provided at opposite sides with flanges, 30 and 3l, adapted for interlocking or overlapping with the fianges of the next adjacent beam, which Iianges form a cut-off for any air which may enter between the beams, and prevent the egress of said air to the space between the upper and lower runs of the grate. t

The mode of `operation of my invention is as follows: The fuel is supplied to the furnace-floor or grate at a point adjacent to the first air-suppl y compartment a upon the gratebars carried bythe beams whose open ends are in communication with said compartment, and is then carried along past this compartment and the succeeding compartments a', 0,2 and a3 with`a slow traveling movement. During this period the combustible material ofthe fuel is consumed, and the result-ant cinder or ash is afterward carried under the place within a short distance of the point where thefuel falls upon the grate, and the fuel being completely reduced to cinder by the time it reaches a point adjacent to the bridge-plate 7. During the traveling movel ment of the grate, the successive traveling floor-beam air boxes receive a supply `of air successively from the successive compartments a, a', (1,2 and d3 at the requisite varying pressures, whence the air is delivered through the discharge-openingsor spaces between grate-bars to the fuel, which is maintained upon the furnace-floor substantially in statu quo during the successive stages of the combustion thereof.

By the construction and organization of mechanism as herein shown and described, I am enabledto secure the best practical results in the combustion of the fuel, and at the same time dispense with air-supply apparatus between the upper and lower runs of the traveling grate.

During operation, should dirt, cinders or fragments of coal fall through the air-spaces into the chambered grate or floor-beam airboxes, they wiil be again discharged owing to the inverting of the beams when they arrive at their lower-run` positions, thus maintaining the cleanliness highly desirable in furnaces of this class.

Itwill be obvious that any suitable means for supplying air to the inletorsupply-openings h, b', b2 and b3, in the side wall of the furnace-chamber, and that any means for regulating the said supply of air, might be employed without departurefrom my invention. t.

By the term air-chambers used in connection with the description of the furnace-licor, it will be understood, is meant the space inclosed `by the side and bottom walls of the floor-beams or iioor-beam air boxes N, said chambers being independent of each other and being connected together to form the endless traveling furnace-Hoor.

Having thus described my invention, I claim 1. In a furnace of the class specified, the combination with the furnace-chamber and its inclosing walls, of a traveling furnacefloor comprising a series ofsuccessive and independent iioor-beam air-boxes each having an inlet opening at one end thereof, means for imparting a traveling movement to the series of floor-beam air-boxes, and an airsupply apparatus adjacent to the inlet openings of and adapted for supplying air to said licor-beam air-boxes, substantially as described.

2. In a furnace of the class specitied,.the combination with the furnace-chamber and its inclosing walls, of an endless traveling furnace-licor or grate having an upper and a lower run and consisting of a series of successive and independent floor-beam air-boxes each having anV inlet opening at one end thereof and having outlet openings through IOO IIO

the fuel-supporting portions thereof, means v for imparting a traveling movement to the furnace-Hoor, and an air-supplyapparatus located adjacent to one edge of the upper run of saidV floor and adapted for supplying air to the air-boxes comprising said floor, sub.

stantially as described and for'the purpose set forth.

3. In a furnace of the class specified, the4 combination with the furnace-chamber and its inclosing Walls, of a traveling furnacedloor comprising-,a series of successive and independentfoor-beam air-.boxes each having an inlet opening atrone end thereofand having outlet openings through the fuel-supporting portions thereof, means for imparting atraveling movementto the furnace-iloonand a variable -pressure air supply apparatus lo-V cated` adjacent to one edge of said furnace.

iioor4 and `adapted for supplying air to the floor-beam air-boxes through the end inlets at varying pressures at successive points in the traveling movement thereof, substantially as described and for the'purpose set forth.`

4t, In a furnace, of the classspecitied, the

combinationwith the furnace-chamber anditsinclosing Walls, of a traveling furnace-floor comprising a series of successive andV inde-v pendent floor-beam air-boxes pivotally con.

nected together and open at the fuel-support ing sides `thereof and each having an inlet.

opening at one end thereof` and a series of gratebars secured -to the open sides of each` bination, a series of transversely-disposed box-like or chambered grate-beams provided with fuel-supporting floor-plates or grate-bars and pivotally connected together to form an endless traveling grate, means for imparting a traveling movement to said grate, and.

means for supplying air to the interior'of successive grate-beams vat successive points in and during the traveling movement of said grate-beams, substantially` as described and for the purpose set forth.

6. In a furnace of the class specified, in combination, a series of pivotally-connected boxlike or chambered grate-beams open at one side and one end thereof and carrying fuelsupporting grate-bars having intermediate air-spaces, means for imparting a traveling movement to the grate-beams, and an airsupply apparatus adjacent to the open ends of said beams and adapted for supplying air thereto during the traveling movement of said beams, substantially as described and for the purpose set forth.

7. In a furnace of the class specified, an endless traveling grate supported by revoluble carriers and comprising a series of pivotallyconnected hollow kbeams V-openat on'e ,end thereof and having fuel-supportingplates or bars with air-spaces in communicationY withA the interiors'of saidbeams, in combination with an air-supply located adjacentto the open ends .of said beams and in communication therewith and adapted for supplying air Ato the interiors of said beams at different pressures at successive points in and during the travel thereof, means in connection with eling movement to thegrate, substantially as n described Vandfor the purpose set forth.

i 8. In afurnace of the class specied, a sebeams each open at one side and at kone `end vries of pivotall'y-connected chambered gratethereof and having gratebar` engaging flanges at the open side thereof,in combination with a Aseries of grate-bars removably engagingthe anges of said grate-beams, substantially as described.

9. In a furnace of the class specifiedthe combination with thefurnace-chamber, of a traveling furnace-floor consisting of a series of independent l grate-Sections connected together, and each section comprising a rectan gular beam .having an inclosed air-chamber-A y and a series of grate-bars or Hoor-plates removably connected with said beam, substanf. tially as described.

10. In afuruaceof theiclass specified, the

IOO

combination with the furnace-chamber having an air supply opening, of a series of independent inclosed traveling air-chambers, having.r fuel-supporting` portions with.. airspaces therein and having inlet openings adapted for successively registering With the air-supply opening in the furnace-chamber during the traveling movement of said cham-v` bers, substantially as described.

1l. Ina furnace of the class specified, a

IIO

grate-section consisting of a rectangular.

chambered beam. open at the end and at one f side thereof and having oppositely-disposed. inwardly-projecting flanges at the open side thereof, in combination with a series of grate-YV bars having, each,a depending flange in movable engagement with the flanges of saidV beams and having abutments at one side thereof adapted to bear against `the side-facc of thenext adjacent grate-bar to form an airspace between adjacent bars, substantially as `described.

. l2. In a furnace of the class specified, the

combination `With the furnace-chamber hav- A ing a series of air-suppl y openings at one side thereof adjacenttc the path of travel of the furnace-floor, of a series of Xed compartments communicating with said supply-openings, n

air-supply pipes communicating With said compartments and having regulating-valves, a traveling furnace-floor comprising a series of independent inclosed air-chambers con-` nected together and. supported inposition to register successively with the air-supply open- Y `ings of `the furnace-chamber, and means for imparting a traveling movement to said furnace-ioor, substantially as described and for the purpose set forth.

13. In a furnace of the class specified, the combination with the furnace-chamber having an air-supply opening through one of the side-walls thereof,`ofatraveling furnace-floor having a fuelsupporting run supported in horizontal alignment with said air-supply `opening in the furnace-chamber and consistdoor-beam and air-box having an inlet opening at one end thereof and having outlet openings extending through the fuelsupporting sides thereof, substantially as described.

15. The herein-described `floor-section for traveling furnace-lloors for furnaces of the class specified, it consisting of a floor-beam airboX open at one end and at one side thereof, and a series of transversely-disposed gratebars removably secured to the open side of said Hoor-beam air-box,substantially as de# scribed.

16. `The herein-described floor-section for traveling furnace-floors for furnaces of the class specified, it consisting of a cross-sectional ly rectangular floor-beam longitudinally recessed to form an air-box open at one side and at one end and having longitudinal fianges at opposite sides thereof adapted for overlapping similar anges upon adjacent fiooubearns, substantially as described.

FRANCIS H. RICHARDS.

Witnessess:

FRED. J. DOLE, RoBT. V. RUDDELL. 

